The role of micturating cystourethrography in antenatally detected mild hydronephrosis

Abstract

Background: The postnatal imaging of infants with antenatally detected mild hydronephrosis remains controversial.

Objective: Our aim was to establish the role and timing of micturating cystourethrography (MCUG) in mild hydronephrosis.

Materials and methods: We performed a retrospective study of 61 infants (122 kidneys) referred with an antenatal diagnosis of hydronephrosis who showed persistent postnatal dilatation. All had follow-up postnatal ultrasound (US) and MCUG performed. The degree of dilatation at each follow-up scan was recorded.

Results: Of the 122 kidneys, 65 showed mild hydronephrosis. A substantial proportion of these (21.5%) demonstrated reflux. Serial US of these infants showed that the 6-week scan was the most informative and that any changes that warranted further investigation had occurred by this time.

Conclusion: We recommend that all infants with mild hydronephrosis should undergo MCUG. MCUG need not be delayed until 3 months but could be performed following a 6-week US scan.